Multiple Modules Bad... These are my favorite!

This 2008 Silverado came in as a very strange Crank No Start. Testing finds multiple modules are bad. How to sort through it? One at a time...
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[@10100rsn]

A crank-in-run-no-start? Fascinating. ;P

[@v8motors.]

If the customer didn't know you and you presented them with your findings that nearly everything is fried & needs replacing, they'd be thinking your trying to pull a fast one. Great diagnosis and diagnostics Jake. 👍🙂

[@autodiagyt]

Not when you have test to prove it!

[@DuaneDonaldson]

Our contract that the customer signs ought to state that on occasion, there is more than one problem, and the second problem cannot be noticed until the first problem is repaired, and in some additional cases, there are more than two problems. With computers, we can then link a couple of videos on the receipt for the owner to view during or after the repairs. This is not the first case of multiple modules going bad. The work order/receipt is there to CYA for any possible legal purposes, annotate everything with time stamps. Even for shops that DO CHEAT us, once we sign our name and give any additional OK via text or phone, etc, the shop has the right to do as they wish. As Jake says, he has the proof, well, proof to him, can NASA disprove him like they did Toyota??? That won't be free so no need to worry about it.

[@eddiereichel9354]

That first crank sure sounds like the AFM lifter has left the building.

[@autodiagyt]

I agree.

[@aranhaydar9195]

You're putting out some of the coolest cases on KZbin!

[@DrFiero]

The FPCM and TBCM's are notorious for getting the green fuzzies inside them. The FPCM I think was the very first thing I fixed when I got my '08! You'd turn on the key, and the rail pressure shot to about 95psi and just stayed there. :O

[@CROFTY71]

FPCM ?TBCM ?

[@benjaminbrower540]

Excellent video.. Great ohms testing with that 4x4 module in relation to testing methods to isolate a problem. Love the videos.. You the man!

[@DrFiero]

Oh yeah, washer fluid low warnings on too. Time to scrap it. :D

[@JBlake-moon-shdo]

Great job walking us through the process Jake. You make it easy to follow. Thanks.

[@scottnusser6232]

With current state of the economy and the interest rates, normal working people are not able to afford 60-80k for a p/u truck. I've been fixing vehicles that should be junked in my opinion,but customers are spending money on them. I think this next period of time will be s hayday for good techs who can do what you just did, get it running! Even if the man puts a motor on it, it's cheaper than a new truck. I've got an 04 silverado, the man has spent, 5k so far with me and next week I'm gonna rebuild the trans and replace the rotten fuel lines, replace rear seal cover also! Counting purchase price and repairs, he'll be in at about 20k, but it ain't 60k. Great diag as usual Jake❤

[@kevinwalker4623]

Throw in the UAW strike and can you even get that 80k truck?

[@gregjones8501]

Bro! Hope all is well! You have such a thorough understanding of there vehicles and their complex systems and it clearly shows! Thanks for bringing us along and taking the time to teach and show us how it’s done!

[@mikechiodetti4482]

Well, you know what your doing, the customer must really like this vehicle! Good one Jake. On to the next problem.

[@v12alpine]

I don't think lightening would cause a loss of compression. I wonder if it's been sitting for a while with a flat cam and someone did the old whoopsie on the jumper cables :P

[@autodiagyt]

No he told the shop that it was running one day and that night there was a storm roll through and the next morning it was trying to start with just the key on.

[@yousseftriaxis4135]

one of the best channels out there

[@djosbun]

That fly was finding your hand awfully sexy, Jake. 👍🏼

[@MattyEngland]

It never fails to amaze me how poorly a lot of these chevys are wired. I know European cars are unnecessarily complex etc, but at least they use high quality connectors and route the wires through high quality harnesses. Looks like GM used ebay connectors and electrical tape on most of these vehicles.

[@Hybriddiag]

Again lightning 🌩 striked 😅...but its way easy to diagnose than a reverse jumped vehicle...thats a real rabit hole 🕳...cheers jake 👍🏿

[@aymenmohamed1134]

Awesome

[@kyletuttle9064]

Cool video again Jake thanks

[@alrifainidal]

As always great job

[@richardcranium5839]

up here in the rust belt some of those things are worth fixing.

[@raviautoscanning]

Thank you.

[@7465mtpa]

i have a ecm out of a 06 dodge 5.9l diesel that needs repair something you can do, love your channel

[@autodiagyt]

Check out Jason at Keyworks ECU Repair he’s pretty familiar with Cummins pcms

[@richardbrooks4597]

Ihi you always have some great contact and very informative. I have a 2015 Benz sprinter van no communication with the ecu and communication with all the other modules I would really appreciate your help. . Thank you

[@autodiagyt]

So you can communicate with everything but the engine computer?

[@JoseSilveira-newhandleforYT]

Great strategy for an excellent diagnostic, Jake! You are getting some lightning struck vehicles lately. Wonder if the truck is worth the repair, with an engine problem on top of the bad modules.

[@autodiagyt]

My thought was no but the guy said he couldn’t replace it for what it was to just fix it and it’s only used on a farm.

[@JoseSilveira-newhandleforYT]

@@autodiagyt Yep. That's a special case and it's understandable.

[@prashanshan7125]

Nice work 💪..!

[@calholli]

Is this that same truck you did multiple videos on before? Or is this a totally different truck?

[@autodiagyt]

Totally different. This one was actually a few months ago and I just never thought it would edit together well.

[@paulburroughs1313]

Built in lightning suppresion (with serious air gaps) might stop this sort of thing. Probably would have to earth the truck's frame after park up as well... Naw, the canbus harness is a giant antenna...just build a garage.

[@autodiagyt]

Can bus transceivers are pretty robust except when it comes to emp lol it seems to get them a lot.

[@Fix_it_right]

Great video as always. What is the purpose of using low amp and high amp test light in testing? Thank you

[@autodiagyt]

Different circuits need different loads. I have a bmw x5 video that shows the value of the high impedance test light. Its very low current so it’s a module safe test light.

[@Fix_it_right]

@@autodiagyt thank you will sure check that video

[@philh9238]

What about a shorted 5 volt sensor causing the no communication with the ecm?

[@autodiagyt]

I've had a lot of shorted 5v ref circuits and haven't ever found it to case a no comm on a gm ECM. They generally run a dedicated 5 and 3v regulator inside the ECM that doesn't work anything external. It still wouldn't explain why the ECM was turning the starter relay on.

[@paulgilliland2992]

Would you please please please make a video on how to use the small 1 or 2 channel mini oscilloscope and go through the steps how to check for a signal from a module?

[@autodiagyt]

Which oscilloscope are you referring to?

[@paulgilliland2992]

Leolov/Zeewii 2 channel portable 120MHz scope . The little blue one that Ivan uses . I hope you have one.

[@autodiagyt]

@@paulgilliland2992 I don’t have one. I’ll see about getting one. From the way it looks on Ivan’s videos it seems pretty good.

[@automotivetechnician921]

I have a Toyota Tundra 2002 model. It is getting two codes. Replaced sensor but problem not solved. Codes are p0135 and p0155. These are the two codes. I have checked all the wires and they are fine too. computer. Replaced that too but problem not solved. What could be the problem. Please help

[@autodiagyt]

I would verify with a test light(at the sensor plug) that I have good power to pin 2 and ground pin 4 with engine running. If that lights up bright then plug the sensor up and go to the ECM and back probe conn E6 pin 4 and use a volt meter connected there and to ground and see if you have voltage. If you replaced the sensors with aftermarket the ECM just might not like the resistance of the heater and the fix just might be OEM sensors.

[@automotivetechnician921]

Yes sir thank you very much۔It was exactly the same problem as you said۔But before you answered I checked the resistance and there was a big difference.Oxygen sensors were to be installed in it۔But it was fitted with air fuel۔So there was a huge difference in their resistance۔But thank you very much for your reply

[@raulpereyra2817]

Would insurance cover the cost of the repair if properly covered and diagnosed?

[@autodiagyt]

Yes but in most cases when insurance hears a diagnosis of lightning they will total it out.

[@astritzyberaj6132]

Looks like you are checking a fladed vehicle

[@joeandgod1]

Did the customer say if he knew if lightning struck it?

[@autodiagyt]

I didn’t really ask. It’s just a very good assumption.

[@joeandgod1]

@@autodiagyt It would be interesting to know for future reference. Or if he put the battery backwards or maybe even flood, low water crossing, who knows.

[@autodiagyt]

@@joeandgod1 in most cases with a battery connected backwards there is almost always blown fuses. This truck had none. He drove it and the next morning it was running the starter in run and he said there was a storm that rolled through that night.

[@PhillipBailey]

I had an 04 duramax that had a near lightning strike where lightning struck a steel shed 8 feet from the truck. It took out the ECM, TCM and ABS modules. I hoped I could get away with just replacing the ABS module but ended up having to replace the hydraulic portion too. Insurance covered the repairs as well.

[@autodiagyt]

@PhillipBailey yeah I try telling people it doesn’t have to be a hit, just be close.

[@deeznutz3494]

I’d like to see some of those modules opened up, if they were all charred inside like the last one.

[@autodiagyt]

This was months ago I didn’t keep the modules from it.

[@PhillipBailey]

When it was cranking I could hear there was a compression issue...

[@autodiagyt]

Yeah pretty sure was a afm lifter. The guy said it's been like that and he didn't care lol

[@crasher88]

Jake can you please explain why you would immediately go into trying to chase a network issue instead of an ignition switch issue? My logic would be if you can't put the key into run then the ignition switch will never fully turn on every circuit and thus fully power up every module creating a no comm situation.

[@autodiagyt]

You could go that way sure, you’ll quickly run into the fact that the ignition switch is tied to the bcm which you can’t communicate with and then it transfers a start command to the ecm over data that you also cannot communicate with. Any way you go you will have to restore communication first. You could even start at the starter relay and see that the ecm was always sending a turn on command and testing would prove the wire isn’t shorted to ground keeping the relay turned on so you would then need to see live data in the ecm to see if it was commanding it on or internally shorted. See it always circles back to the correct thing to be testing.

[@ebolti22]

@@autodiagyt "You can even start with the starter relay and check that the ECM always commands ON, and the tests will show that the wire is not shorted to ground, keeping the relay ON, so you will need to see the current data in the ECM" - - Did you make a mistake here by writing, that a cable with a shorted ground will cause the starter to run all the time?

[@autodiagyt]

@@ebolti22 this was several months ago and I can’t remember the car at all.

[@artursmihelsons415]

This one was pretty crazy! I never seen before in modern cars crunking in run mode.. 😂 Excellent video and nice job with great diagnostic! 👍 My second thought was that fuel pump module is guilty and caused short for bus, because in trucks, it's a weak spot, but I can't explain, without checking, why starter relay is engaging in run position.. Lightning and lots of dead modules explains everything.. 😬

[@JK-zl7vv]

Sometimes what you get, are vehicles that have been submerged in water, then dried back out, so you dont have signs of water damage, but all of the control modules are wiped out like this vehicle is. 🤔🧐

[@bartscave]

You get some unbelievable diagnostic nightmares!! Love following your trouble shooting process through these cases. Sooo glad these aren’t in my shop though!

[@spirokattan3655]

Jack, Another great diag and lesson on Bus troubleshooting. Thanks for posting! You are awesome!

[@moog2961]

Best video to date. Brilliant work. X

[@paulrunell7821]

wow that truck is cleaner underneath than in the cab

[@charliemagoo7943]

Was it on your channel they showed why you might get 58-64 ohms when combining the two 120 resistors and never 60 spot on???

[@autodiagyt]

I don't think so but yeah it's rare you get exactly 60 because length of wire and connectors will increase resistance and also resistors have a tolerance. 58-62 is pretty normal and I've seen as high as 72. GM(and most others) actually has their system designed to only need 120 and have successful communication, the signal on a scope will just be noisy.

[@DependableAutoTruck]

great video thanks for sharing

[@wilamyoukhana1109]

It’s hard task good job buddy

[@paulspeller968]

oh wow one of those new auto cranking cars🤣🤣🤣🤣 well that turned into found a dead short module into a whole world of pain . excellent diagnosis my friend and looked like a good gray matter work out 😱

[@imfloridano5448]

This is the chilliest mechanic around. Make me think Delta 8 or Delta 9 may be his daily supplement 🤣🤣😂😂🤣. I take Delta 8 at night for pain daily in 1-3mg

[@autodiagyt]

Lol no I'm not a fan of that stuff 🤣

[@cullenmiller8170]

Great video and diagnosis. You guys must have a lot of lightning or you just have bad luck and get all the ones that got lit up. 😂😂

[@autodiagyt]

I don’t mind lol

[@marcokahny709]

If that was my truck I would take it to Scotty Kilmer 😂

[@autodiagyt]

Do he ever even diagnose anything in his channel?

[@waqasazmat81]

Thanks for sharing definitely helps when it comes to tackling network issues.

[@advancedleveldiagnostics]

Another great diag, Thanks for sharing!

[@jtjones4727]

That's a nice hack there, letting the air out of that spare tire. Those spares can be a bear to drop down sometimes, especially after 15 years or more. GM loves to put modules on top of those.

[@roxanneabbott8424]

I love these kinds of videos, thank you Jake!!

[@NoName-yr1jv]

Well done 👍

[@martinsheanon3232]

lip sync again

[@autodiagyt]

?